Sighting attachment for carpenters&#39; squares.



T. 1. SMITH.

SIGHTING ATTACHMENT FOR CARPENTERS SQUARES.

APPLICATION FILED JULY I, 1915.

1,210,997. Patented Jan. 2,1917.

@FWTQE.

THOMAS J. SMITH, or PONTIAC, MICHIGAN.

SIGHTING ATTACHMENT FOR CARPENTERS SQUARES.

Specification of Letters Patent.

Patented Jan. 2, 1917.

Application filed July 1, 1916. Serial No. 107,088.

To all whom it may concern: I

Be it known that I, THOMAS J. SMITH, a citizen of the United States, residing at Pontiac, in the county of Oakland and State of Michigan, have invented certain new and useful Improvements in Sighting Attachments for Carpenters Squares, of which the following is a specification, reference being had to the accompanying drawings.

This invention relates to carpenters squares and more particularly to sighting attachments therefor.

The general object of my invention is the provision of sighting attachments to be used with steel squares whereby sights may be taken to any desired distance at right angles to each other the attachments being useful in a large number of diiferent circumstances but particularly useful in laying out foundations, staking out square plots of ground and in taking sights along buildings.

A further object of the invention is the provision of attachments comprising a pair of rear or peep-hole sights with means for attaching the sights upon the corner of the square and front sights with means for slidingly engaging them with the tongue and blade of the square.

Other objects will appear in the course of the following description. 1

My invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of a square with my attachments applied thereto; F ig.

2 is a section on the line 22 of Fig. 1; Fig. 3 is a section on the line 33 of Fig. 1; Fig. 4 is a top plan view of a front sight;

' and Fig. 5 is a top plan view of the corner sight.

Referring to these figures A designates a carpenters square having the usual tongue and blade. My attachment comprises a pair of peep-hole sights disposed at right angles tov each other and so mounted that they may be connected to the square at the corner thereof and a pair of forward sights each one used in connection with one of the peephole sights. The peep hole sights are mounted as follows: 10 designates an angular plate providing two legs 11 and 12 at right angles to each other. Each of these legs is provided at its ends with a thickened portion or lug 13, the outer half of which extends upward as at 14. The inner end of each leg is provided also with a thickened lug 15, the outer half of which extends upward as at 16. These upwardly extending portions 1a and 16 on both legs constitute abutments adapted to bear against the edge of the steel square as illustrated in Fig. 1, while the faces of the slightly thickened portions or lugsbear against the under face of the square and give a four-point bearing for the square upon the base of the attachment. It will of course be understood that the faces of the abutments 14: and 16 on one leg are at right angles to the faces of the abutments 14 and 16 on the other leg. Extending at right angles to each other are the arms 17 and 18, which arms are upwardly turned as at 19 into a vertical plane and are formed with the concavities 20 and with the small peep-hole 21, the concavities' being upon the outer face of the arms 17 and 18. The axes of these peep-holes are of course at right angles to each other and when the attachment is in place, these axes are parallel to the blade and tongue of the square respectively. The arms 11 and 12 are formed with upwardly extending lugs 22, upon which are mounted spring clips 23 which are adapted to extend over the square and bear resiliently upon its upper face.

The forward sights are each composed of a'base 24, having an upwardly extending flange 25 along its rear edge, the base being approximately triangular in form and provided with an upwardly extending stud or lug 26 at its terminal. From the middle of the flange 25 there extends upward an approximately triangular sighting member 27, this member 27 being braced in its upright position by means of the bracing web or flange 28 which extends downward and then at right angles below the base as at 29. At the forward and rear extremities of the base there are formed the slightly thickened lugs 30 which have the same thickness as the lugs 26 and rest upon the under face of the square, thus the base 24: has a threepoint bearing upon the under face of the square. Mounted upon the flange 25 are the spring clips 81 which bear upon the upper face of the square. It will be seen that the flange 25 bears against the rear edge of the square and that when one of the forward sights is in position upon the square, the edge of the sighting member 27 will be in exact alinement with the axis passing through the corresponding peephole 21.

The use of my attachment will be obvious in thedrawings. The several parts of my sighting device may be readily applied to the square or as readily removed and as the attachments are extremely simple, there is no likelihood of the parts being broken or getting out of shape. The device may be readily applied either to small squares or the larger type of steel squares and it is obvious that the fore sights may be set any desired distance from the peep-hole sights so as to secure a corresponding degree of accuracy in the setting of thesquare. It is also of course obvious that the axes, that is the lines extending from the peep-holes to the respective fore sights, will be exactly at right angles to each other. It is an easy matter with these attachments to establish foundation lines, lay out plots of ground or lay out large rectangles, operations which would otherwise be diflicult to perform with the ordinary square. A hook eye 32 which is attached to the under side of the base at a point directly under the corner of the square permits of the attachment of a plumb bob. It is to be noted that the finished lugs and faces which bear against the edge and face the square are so arranged with'relation to each other that they may be machined all at one operation, thus making it certain that the faces lie in one plane.

Having described my invention, what I claim is:

1. Sighting attachments for squares comprising a rear sighting member having a base formed with abutments disposed at right angles to each other and adapted to engage the corner of the square, and a fore sight having a base formed with an abutment adapted to engage the edge of the square and having a sighting member coacting with the first named sighting member.

2. Sighting attachments for carpenters squares comprising a rear sighting member having a peep-hole, said sighting member having a base formed with abutments disposed at right angles to each other and adapted to engage the corner of the square, and a fore sight having a base formed with an abutment adapted to engage the edge of the square and having a sighting member coacting with the peep-hole sight.

3. Sighting attachments for carpenters squares comprising a rear sight having a Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

base adapted to engage the corner of a square and be held thereby at right angles to one of the edges of the square, and a fore sight adapted to be detachably mounted upon one of the blades of the square.

4. Sighting attachments for carpenters squares comprising a rear sighting member consisting of a base having abutments disposed at right angles to each other and adapted to engage against the outer edge of a carpenters square, said base having means for detachably holding it upon the square and being provided with'arms extending upward and in planes at right an gles to each other,'each of said arms being formed with a peep-hole sight, and fore sights one for each blade of the square comprising a base formed with'an abutment adapted to bear against the edge of the square and with an upwardly extending, sighting member and with means for de-' tachably and slidably engaging it with the corresponding blade.

5. Sighting attachments for carpenters squares comprising a rear sight and a pair of fore sights, the rear sight comprising an approximately triangular base having upwardly extending lugs upon its surface adapted to bear against the under face of o the square and having upwardly extending abutments disposed at right angles to each other and adapted to bear against the outer edges of the square and also formed with upwardly extending arms disposed in planes at right angles to each other and parallel to the outer edges of the square, each of said arms being formed with a peep hole, and spring clips mounted upon the base and engageable with the face of thesquare, the

fore sights each comprising a base hav- Washington, D. G. 

